Process and apparatus for compressing coal in a chamber oven; retorts and the like



May 28, 1935. H. PE'rscH 2,002,614

Pnocmss `AND APPARATUS FOR coMPREssING coAL IN A CHAMBER OVEN; RETORTSAND THE LIKE4 Z'Sheets-Sheet l Filed Sept( 18. 1931 H. PETscH A2,002,614 P ESS AND APPARATUS FOR COMPRESSING COAL A CHAMBER OVEN', RETS AND THE LIKE Filed Sept. 1951 2 Sheets-Sheet 2 May 28, 1935.

s Patented May28, 1935 n A.

- PROCESS AND APPARATUS FOR'COMPRSS- ING COAL IN A CHAMBER OVEN; RETORTSAND THE Hermann Petsch, Recklinghausen, Germany, as-

signor to the Firm CarlA Still, Recklinghausen,

Germany Application September 18, 1931, Serial No. 563,648

` InGermany September Z3, 1930 8 Claims. (Cl. 2025-36)l The inventionconsists in a process'and apparatus Lfor mechanically compressing, toany required extent, coal charged loosely into chamberv ovens,cake-forming boxes or `other rigid receptacles.'` e

The accompanying drawings represent devices and `rxieans for carryingout the process.

Fig. 1 represents, as an example ofthe application of the process toahorizontal chamber oven for the production of gas and coal, a verticalsection of an oven chamber of this type, including also the hoppersprojecting downwards from a charging car adapted to ,travel over theoven, the upper portion of the figure being an elevation of the chargingbox and gearing used in carrying out the process. "Fig. 2 showsdiagrammatically one of thecompressing screws 23. lFig. 3 is Va detailedview of the beam carrying the compressing elements and shows the mannerin which it is supported by and driven along the vertical frame members,in a modiedform of the invention;

Fig. 4 is a detailed view of one of the compressing screws; l a l Fig 5is aview on line V-V of Figure 4.

rIfhe reference I representsthewovenchamber which'is closed on bothsides bythe doors 2, is bounded abovel by `the oven roof 4V and containsthe charge3 of loosely inserted coal. Six charging openings 5 and theusual lgas withdrawal opening 6, on which anascension pipe isplaced, areprovided in the oven roof 4.j A coal charging car 33"of any well knownconstruction, but with the additional equipment to be herein described,travels on rails over the ovenrooi`4. The charging car`33 is providedwith a coal' bunker 1 disp charging in commonintosix downwardly pro-ljecting compartments 8 acting as hoppers. The discharge openings 9 ofthe hoppers 8 are so spaced as to permit them to be positioned di-`rectly over thecharging openings 5 in the oven roof. 5

A framing, connectedto the box 1, comprises two vertical guides I0connected by an upper horizontal transverse member II and 'serves forguiding in its vertical movement`a horizontal girder I2. The latter isguided lat the vertical parts III of the framing by rollers I3, of whichat least one on each side may be formed as toothed wheels and engage incorresponding `racks. arranged at the guides I0 as shown in Fig. 3. lIwocables I4, connected to the girder `I2 and led over guide rollers I5secured to the transverse member II, serve, by means of a winding gear29 driven by a variable speed motor wheel 22 which meshes with a gear 2lkeyed to pressingtool 23.

30, to raise and lower the girder. The girder I2 may also beraised andlowered by means of the arrangement shown in. Figure 3 in which, insteadof cables, a variable speed motor 3| is carried by the girder and isconnected bymeans of `a 'chain'and sprocket arrangement to drive thepinions I3. Adjustable counter-weights are at- Ajtached to the cables topartly balance the weight `f of the girder. If the toothed wheels andrack gearing are provided between theparts I3 and I0, they can serve bymeans of a variable speedmotor 3l or other suitable machine to impart apositive upward and downward movement to'the girder I2. Instead of thetoothed'wheels and rack gearing a chain wheel with a driving chain canalso be provided. Six vertical shafts I1 are suspended in bearings I6from the girder I2 and a bevel gear wheel I8 `is connected to `the upperend of each shaft. This number of six is optional; a larger number wouldusually `be preferable. Other bevel gear wheels I9 serve to operate thevbevel gear wheels I8 and are disposed on a shaft 2i common to the wholegirder and supported in bearing blocks 20; The `shaft 2l carries a gearthe shaft of motor 28. v p

The shafts I1 project downwards through the hoppers 8 and the chargingopenings 5 in the oven Aroof into the oven chamber I and carry at theirlower ends helically or spirally formed compressing members e. g. wormsor screws 23 shownin detail in Figure 4 ,which act as the actualcompressing tools. In the example shown in the drawings, the axallengthof the worm is less than the depth of the)charge 3 of coal. The axialcross-section of 'the helical surface orthread of the worm is preferablytriangular, the under side voijthe helical surface of the worm isinclined upwards from the axis and may also be curved, so as to vform aconical surface, of which thevertex is directed downwards. The externaldiameter of the worm is preferably reduced at both ends, viz; isgreatest at the central portion. It may also be cylindrical whereas theshaft of the worm is conically enlarged towards its end. Instead of theturn of the Ascrew a spiral of Archimedes vor a multiple thread screwmay be used. Close to the ,position in which a worm 23 is connected tothe -shaft'll there is a stirring blade 24 (Figures 4 and 5), thegreatest radial extension of which is greater than the largest radius ofthe comi The blade 24 may extend to a distance greater than the radiusof the charging opening 5. `In this case it is necessary, in other casesit is advisable, to construct the blades so 55 that, during theirpassage through the charging openings 5 and the discharge openings 8,viz. during the introduction and withdrawal of the worms 2l, they arehinged so as to lie closely against the shafts I1.

The suspension of the shafts I'I at their upper ends in the bearings I6and their gearing are preferably arranged so that the shafts II and withthem the worms or spirals 23 are shaken during their vertical movements.This can, for example, be effected by the arrangement in whicheachsupporting ring of the bearings I6 has a waved or sinuous contourinstead of a plane surface, and these surfaces from the races of ballbearings. Care must naturally be taken that these vertical impulses arenot imparted to the bevel gear wheels I8, or that by suitableconstructions they do not injuriously affect the operating gearing. 1

The described arrangement is operated as follows:

The girder I2 with it all the worms 23 is raised into its highestposition in which the worms are outside the oven chamber I, or thegirder is lowered until the worms are just below the charging openings5, and coal is looselyinserted in the usual manner from the box 'I ofthe charging car through the hoppers 8 and the openings 5 into the ovenchamber I, forming projecting conical piles 25 of loose coal on thecharge 3. In this condition, parts of the coal charge extend into theopenings 5 and even into the hoppers 8, as

shown in Fig. l.

The girder I2 with all the .worms and worm shafts connected to it isguided vertically downwardsand the shafts I'I are set in rotation by themotor 28 operating the gearing 22. If, as shown in the drawings, thethreadsof the screws 23 are right-handed, during this working stage aright- .handed rotation, as seen from above, is employed.

The worms are simply screwed like corkscrews into the charge 3, sincetheir weight is counterbalanced, they are unaiected byA frictionalresistance and descend freely, that is, without any mechanical pressure.In order, according to the invention, to compress the coal inthe'chamber,

.care must be taken that simultaneously with the downwards movement ofthe worms, the charge must be displaced not only both downwards in thedirection of the axes of the worms, but also laterally outwards, that isradially from the axes of the worms. This can be effected simply by thearrangement in which the worms are pressed downwards by a denite portionof their own weight and that of the supportingy girder. The effectiveportion of this weight can, for example, be adjusted by the amount ofbalancing weight applied to the cables I4. Since the under side of thevhelical thread -of each worm 23, as above mentioned, is inclinedconically upwards, when a .pressure is exerted on the worm from above,not only a downward component, but also a lateral component, of thepressure is exerted within the charge of coal. By their rotationalmovement and the simultaneously downward pressure, the worms are drawnfrom their highest position to the bottom of the oven chamber I.

When this condition is attained, the gear operating the rotationalmovement of the worms and the simultaneously downward movement of -thegirder I2, if it is in action, is stopped and the direction of rotationis reversed, that is, the right-handed screw threads 23 are now rotatedAto the left and screw themselves upwardly out of the charge. If duringthis upward movement, the worms are pressed down, for example by theweight of the parts, the coal is compressed dur-4 ing this path in thesame direction as previously duringthe downward path of the worms.

It is advisable to arrange so that the amount of the effective weight isdifferent in the upward and downward paths of the compressing tools.

Instead of using the action of the weights, the worms can be presseddownwards mechanically. In this case, the worms are rotated and an up-Lward and downward motion also imparted to the girder I2 by suitablegearing, the ratio of gearing between their movements being adjustable,or by the positive action of the variable speed motor drive of Figure 3.A movement is effected, which applies also to the previously describedcase in which the worms are loaded by the weights, as showndiagrammatically in Fig. 2. A point A on the periphery of the helicalsurface of the screw-thread, if there were only a rotational movement ofthe worm, as in the case in which the worm is entirely relieved of theweights, would in descending traverse the path A-B, on ascending thepath A-C. Il' sutlicient movement in the axial direction is imparted tothe worm simultaneously with the movement of rotation, there is an axialacceleration, that is worm moving downwards during one rotation isto adistance greater than the pitch of the thread, the point A moving in thepath A-D; and, if there is a retardation in the upward movement, thepoint A follows the path A-E.

Fig. 2 shows clearly that, in the process according to the invention, inboth the downward and upward movements of the worm, the coal isdisplaced axially downwards. Also, obviously whatever may be thecross-sectional form of the worm thread, the coal is displacedlaterally, that is radially outwards from the axes of the worms. Thislateral displacement of the coal is assisted if the under side of theworm thread is inclined upwards, so as 4to form arconical surface. Bysuitably selecting the inclination, the components displacing the coaldownwards and laterally can be varied to a certain extent.

If the worms, as'in the example illustrated, have an axial lengthcorresponding to a fraction of the height of the charge of coal, theytraverse in their upward and downward movements in succession differentlayers of the charge which are, therefore, continuously compressed orprepared for compression. In order to ensure the continuance ofA thisaction during the further movement of the worms, there must be asubsequent displacement of the coal in the direction from abovedownwards. If, as shown in the drawings, the upper. surface of the coalforms loose conical piles, andthe coal Aextends through the chargingopenings 5 into the hoppers 8, fresh coal slides down automatically intothe charge as the worms press the mass downwards. This downward slidingaction can be increased by the stirrer blade 24. This blade stirs thecoal always at the places where it is favourable to form cavitiesdirectly above the screws 23, and, consequently, ensures, even in thiscase, that fresh coal is constantly shaken down.

When the worms are forcibly raised and lowered it is advantageous toimpart a shorter acceleration and retardation inthe lower positions ofthe worms than in the higher, that is to vary the acceleration orretardation during the vertical path. By suitable constructions, such asratio changing gears or the variable speed motor 28, this can beeffected when the worms are acted on by the weight. 'Ihis method ofwork- -mass of coal in said oven in substantially the ing compensatesfor the decreasing or variable compression of the charge of coal frombelow upwards, which would occur without such measures.

When several worms are operating at the same time care should be takenthat the fresh coal is uniformly supplied to all the worms. In thearrangement shown in the drawings this is effected,

for example,` by distributing devices applied between the coalcontainerv 1 and each of the hcp- "pers 8, which ensure a uniform supplyof "fresh coal to the individual hoppers 8; such devices v may be slideswhich are always opened by a coupled gearing to the same'extent.

By the above-described devices, which may also produce the impulsesimparted to the worms 23 or the shafts I1 the compressive action exerteddirectly by the worms `can be strengthened. 'Ihe vibrations imparted tothe worms are transmitted to the surrounding charge of coal and cause itto be packed. The vibrations imparted to the worms can be exerted, notonly as described above, in the axial direction, but also laterally.`

In this case, the upward and downward movements of the worms through themass of coal can be repeated several times. By this, and similarly byvarying the amount of the acceleration or retardation of the worms or ofthe pressure exerted downwards in the axial direction, the coal can bemore and more compressedluntil the required degree of compression isattained.

The method of working can be modified as followst- The compression canbe commenced when the worms 23 are in their lowest position on the soleof the oven chamber I, the coal being gradually charged through openings5, while the worms 23 are screwed upwards and according to the inventionunder retardation at that time. In this way fresh coal is constantlycharged to the places, at the upper end or the upper part of the worms,from which the coal is continuously removed and forced downwards to becompressed. Also, in this method of operation, in which the compressioncan be completed by a single upward movement of the worms, fresh coal ispreferably charged through the different hoppers 8 to all the worms 23uniformly, according the slope of the oven chamber l.

It is not absolutely necessary that the lengt of the worms 23 should beless than the height of the mass of coal to be compressed, or the pathtraversed by the worms in compressing the coal. It is possible touseworms extending over the whole vertical dimension of the charge ofcoal.

'I'he invention is also not restricted to using the worms in thevertical position. By the provision of suitable arrangements forsupplying fresh coal in the space available for the reception andcompression of the coal, under certain circumstances the worms may havepositions other than vertical, for example horizontal or inclined.

What I claim is:-

1. In apparatus for compressing coal charged loosely into a chamber ovenhaving a roof and spaced charging openings therein, comprising meanscarrying a plurality of spaced spirally formed compressing elements inregistration with said charging openings and adapted to besimultaneously introduced through said openings 1n said roof and intocontact with said coal, means for simultaneously rotating said elementsand means for moving said elements into and out of a `same horizontalplane.

` 2. In apparatus for compressing coal charged loosely into a chamberoven having a roof and spaced charging openings therein, comprising aframe disposed over said roof, a cross girder movable vertically intosaid frame, a plurality of spaced spirally formed compressing elementssuspended from said cross girder in registration with said chargingopenings'and adapted to be simultaneously introduced through saidopenings in said roof and into contact with said coal, and meansdisposed on said girder for simultaneously rotating said elements incommon into and out 'of the charge of coal in said oven, and means forraising and lowering said girder.

3. In apparatus for compressing coal charged loosely into a chamber ovenhaving a roof and spaced charging openings therein, comprising acharging car adapted to travel over said roof, a frame attached to saidcar, a cross girder movable vertically in said frame, a plurality ofspaced spirally formed compressing elements suspended from said crossgirder and adapted to register with said charging openings and to besimultaneously introduced through said openings in said roof and intocontact with said coal, means for simultaneously rotating said elements,and means for moving said elements into and out of said coal insubstantially the same horizontal plane.

4. In apparatus for compressng coal charged loosely into a chamber ovenhaving a roof and spaced charged openings therein, comprising a chargingcar adapted to move over said roof, a frame attached to said car, across girder, guides forming part of said frame for guiding said crossgirder for vertical movement, a horizontal shaft carried by said girder,means for rotating said shaft, a plurality of spaced vertical shaftsgeared to said horizontal shaft for rotating at the same speed andsuspended from said cross girder adapted to register with said chargingopenings and to be simultaneously introduced through said openings insaid roof and into contact with said coal, a spirally formed compressingelement fixed for rotation at the end of each vertical shaft, and meansfor raising and lowering said girder vertically to move said elementsinto and out of said coal in substantially the same horizontal plane.

5. In the process of carbonizing coal, the step of compressing a chargeof coal forrcarbonization which consists in charging coal loosely into achamber with rigid walls and bottom, simultaneously moving spirallyformed compressing ele ments into the chamber and into contact with saidcoal at a plurality of spaced points and then rotating said elements insubstantially the same horizontal plane to apply a compressive force tosaid coal which distributes pressure in both a vertical andsubstantially horizontal direction to obtain a uniform compression ofthe entire charge.

6. In the process ofcarbonizing coal, the step of compressing a chargeof coal in a chamber with rigid walls and bottom which consists insimultaneously moving spirally formed compresstarded rate of speed toobtain a uniform compression of he entire charge in both a vertical andVsubsta `tially horizontal direction.

'7. In the process of carbonizing coal, the step of compressing a chargeof coal for carbonization whic consists in charging coal loosely into achamber with rigid walls and bottom, simultaneously moving spirallyformed compressing ele-- ments downwardly into said chamber and intocontact with said coal at a plurality of spaced points, continuouslyrotating said elements while lowering them in substantially the samehorizontal plane with accelerating speed to obtain a uniform compressionof the entire charge in both a vertical and substantially horizontaldirection.

8. In the process of carbonizing coal, the step of compressing a chargeof coal for carbonization which consists in charging coal loosely into achamber with rigid walls and bottom, simultaneously moving spirallyformed compressing' elements downwardly intothe'chamber and into contactwith said coal'at a plurality of spaced points and in substantially thesame horizontal plane, continuously rotating said elements whilelowering them with accelerated speed and while vertically withdrawingthem with gradually retarded speed to obtain a uniform compression ofthe entire charge in both a vertical and substantially horizontaldirection.

' HERMANN PETSCH.

